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| #1012121 (Received by flhurricane at: 11:05 AM 13.Aug.2020) TCDAT1 Tropical Storm Josephine Discussion Number 8 NWS National Hurricane Center Miami FL AL112020 1100 AM AST Thu Aug 13 2020 A just-received ASCAT overpass showed an area of 35-40 kt winds about 70 n mi north of the center of Tropical Depression Eleven, and based on this the cyclone is being upgraded to Tropical Storm Josephine with an initial intensity of 40 kt. Satellite imagery shows that the convective pattern associated with Josephine has become a little better organized since the last advisory, with a ragged central convective feature and a weak band in the northern semicircle. The initial motion is now west-northwestward or 295/13 kt. Josephine should continue this motion for the next several days as it moves toward a weakness in the western portion of the Atlantic subtropical ridge. The global models forecast the western end of the ridge to weaken even more after 72-96 h, which should cause the cyclone, or what is left of it by that time, to turn northwestward. The track guidance is tightly clustered, and the new forecast track lies a little to the right of the previous track and a little to the left of the consensus models. Some additional strengthening appears likely during the next 24- 36 h as Josephine moves through an environment of light vertical wind shear. After that, the cyclone is expected to encounter moderate to strong southwesterly shear as it approaches an upper-level trough over the southwestern Atlantic, which should cause at least some weakening. The new intensity forecast is adjusted upward for the first 72 h based on the current intensity. After 72 h, it shows weakening similar to the previous forecast, but not as drastic as the global models that show the storm degenerating to a tropical wave before 120 h. Josephine is the earliest tenth tropical storm of record in the Atlantic, with the next earliest tenth storm being Tropical Storm Jose on August 22, 2005. FORECAST POSITIONS AND MAX WINDS INIT 13/1500Z 13.7N 49.2W 40 KT 45 MPH 12H 14/0000Z 14.5N 51.1W 45 KT 50 MPH 24H 14/1200Z 15.8N 53.6W 50 KT 60 MPH 36H 15/0000Z 17.1N 56.3W 50 KT 60 MPH 48H 15/1200Z 18.5N 58.9W 50 KT 60 MPH 60H 16/0000Z 19.9N 61.3W 45 KT 50 MPH 72H 16/1200Z 21.3N 63.6W 40 KT 45 MPH 96H 17/1200Z 24.0N 67.0W 30 KT 35 MPH 120H 18/1200Z 27.0N 68.0W 25 KT 30 MPH $$ Forecaster Beven |